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Service bulletin FSB 284-057

A bulletin is a manufacturer's communication to its dealers, as NHTSA indexes it. The summary is NHTSA's. The document is the manufacturer's: read it at NHTSA. A bulletin is not a recall, and listing a model year does not mean every vehicle of it is concerned.

The communication, as NHTSA indexes it (as of 2026-10-19)
TypeService bulletin
NHTSA id10083064
Published by NHTSA2016-10-20
Manufacturer's numberFSB 284-057
Manufacturer's date2015-05-28
NHTSA componentENGINE

NHTSA's summary

HIGH SOOT OUTPUT. ON COLD START UP IN AMBIENT TEMPERATURES OF -4°C (25°F) OR LESS, MACK ENGINES MAY EXPERIENCE ROUGH RUNNING AT LOWER THAN NORMAL BASE IDLE SPEED. UNDER THESE CONDITIONS, EXCESSIVE SOOT IS BEING PRODUCED BY THE ENGINE AND MAY RESULT IN DPF CLOGGING AT A VERY RAPID RATE.

The document

No address for NHTSA's copy can be built for this communication. Ask the dealer for it by the manufacturer's number.

Components

Engine

Vehicles listed
MACK CHU2015 to 2016
MACK CXU2015 to 2016
MACK GU2015 to 2016
MACK LEU2015 to 2016
MACK MRU2015 to 2016
MACK TD2015 to 2016

Listing a model year does not mean every vehicle of it is concerned: the document says which.